U.S. patent application number 09/800788 was filed with the patent office on 2002-02-21 for electrotherapy apparatus and its electric energy delivering method.
Invention is credited to Akiyama, Naoto, Inomata, Masahiko, Tsumura, Ikuhiro.
Application Number | 20020022867 09/800788 |
Document ID | / |
Family ID | 18582889 |
Filed Date | 2002-02-21 |
United States Patent
Application |
20020022867 |
Kind Code |
A1 |
Akiyama, Naoto ; et
al. |
February 21, 2002 |
Electrotherapy apparatus and its electric energy delivering
method
Abstract
The apparatus is structured in such a manner that, when the
waveform of the electric energy outputted from the output
electrodes 112a and 112b is the positive phase, the inductor 105,
electric energy storage section 104, the first switch means 101,
output electrode 112a, patient 113, and the output electrode 112b
are connected so that these can form the closed circuit, and in the
case where the waveform of the electric energy outputted from the
output electrodes 112a and 112b is the negative phase, when the
first switch means 101 is closed, the inductor 105 and the electric
energy storage section 104 form the closed circuit, and when the
first switch means 101 is opened, the inductor 105 and the electric
energy storage section 104 are electrically separated, and the
delivery of the electric energy to the output electrodes 112a, and
112b is conducted by the inductor 105.
Inventors: |
Akiyama, Naoto; (Tokyo,
JP) ; Inomata, Masahiko; (Tokyo, JP) ;
Tsumura, Ikuhiro; (Tokyo, JP) |
Correspondence
Address: |
SUGHRUE, MION, ZINN, MACPEAK & SEAS, PLLC
2100 Pennsylvania Avenue, N.W.
Washington
DC
20037
US
|
Family ID: |
18582889 |
Appl. No.: |
09/800788 |
Filed: |
March 8, 2001 |
Current U.S.
Class: |
607/66 |
Current CPC
Class: |
A61N 1/3956 20130101;
A61N 1/3912 20130101; A61N 1/3937 20130101 |
Class at
Publication: |
607/66 |
International
Class: |
A61N 001/36 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 8, 2000 |
JP |
2000-62942 |
Claims
What is claimed is:
1. An electrotherapy apparatus comprising: an electric energy
storage section generating a stimulation pulse, and an output
electrode for applying the stimulation pulse to a patient; means
for reversing polarity of the voltage outputted to the output
electrode, and outputting at least first phase waveform and second
phase waveform to the output electrode, controlling the shape of
the second phase waveform.
2. An electrotherapy apparatus comprising: an electric energy
storage section generating a stimulation pulse; an output electrode
for applying the stimulation pulse to a patient; means for
reversing polarity of the voltage outputted to the output
electrode, and outputting at least first phase waveform and second
phase waveform to the output electrode, a predetermined electric
energy being delivered within a predetermined time period in the
second phase waveform.
3. An electrotherapy apparatus according to claim 2, further
comprising: control means for controlling the apparatus such that
the electric power of the electric energy outputted from the output
electrode becomes constant without depending on a value of the
impedance of the patient during the output period of the second
phase waveform.
4. An electrotherapy apparatus according to claim 3, wherein the
control means controls the output so that the value relating to the
voltage, which is lowered corresponding to the amount of the energy
supplied from the electric energy storage section, changes
corresponding to a function of the predetermined time period and
the value relating to the voltage.
5. An electrotherapy apparatus according to claim 4, wherein the
value relating to the voltage is one of a voltage value, voltage
differential value, and voltage double differential value.
6. An electrotherapy apparatus according to claim 3, wherein the
control means controls the output so that the value relating to the
current, which varies corresponding to the amount of the energy
supplied from the electric energy storage section, changes
corresponding to a function of the predetermined time period and
the value relating to the current.
7. An electrotherapy apparatus according to claim 6, wherein the
value relating to the current corresponds to one of a current
value, current differential value, and current double differential
value.
8. An electrotherapy apparatus according to claim 2 further
comprising: patient parameter measuring means for measuring the
patient parameter; output electrode parameter measuring means for
measuring the voltage generated between the output electrodes, or
the current flowing to the output electrode; and control means for
controlling the apparatus such that the electric power of the
electric energy becomes constant without depending on a value of
the patient impedance on the basis of the patient parameter
measured by the patient parameter measuring means before the second
phase waveform is outputted and a value, which relates to the
voltage between the output electrodes or the current flowing to the
output electrode, measured by the output electrode parameter
measuring means during the output of the second phase waveform.
9. An electrotherapy apparatus according to claim 2, further
comprising: an inductor; an electric energy storage section; first
switch means for connecting the electric energy storage section,
wherein when the waveform of the electric energy outputted from the
output electrode is the first phase waveform, an inductor, electric
energy storage section, the first switch means, the output
electrode, patient, and at least, another output electrode are
connected to form a closed circuit, wherein in the case where the
waveform of the electric energy outputted from the output electrode
is the second phase waveform, when the first switch means is
closed, the inductor and the electric energy storage section
without the patient form the closed circuit; and wherein when the
first switch means is opened, the inductor and the electric energy
storage section are electrically separated, and the electric energy
is delivered from the inductor to the output electrode.
10. An electrotherapy apparatus according to claim 9, wherein the
shape of the second phase waveform can be controlled by switching
the first switch means.
11. An electrotherapy apparatus according to claim 9, further
comprising: second switch means and third switch means for shaping
the first phase waveform and the second phase waveform of the
electric energy outputted from the output electrode.
12. An electrotherapy apparatus according to claim 11, wherein the
first switch means, second switch means and third switch means are
structured by semiconductor switches.
13. An electrotherapy apparatus comprising: an electric energy
storage section generating a stimulation pulse; an output electrode
for applying the stimulation pulse to a patient; and control means
for controlling the shape of the waveform of the stimulation pulse
such that the predetermined electric energy stored in the electric
energy storage section is outputted to the output electrode through
an electric circuit within a predetermined time period.
14. An electrotherapy apparatus according to claim 13, wherein the
control means controls the shape of the waveform of the stimulation
pulse in such a manner that the electric power of the electric
energy applied from the electrode becomes constant without
depending on the value of the impedance of the patient.
15. An electrotherapy apparatus according to claim 14, wherein the
control means controls the output in such a manner that the value
relating to the voltage which is lowered corresponding to the
amount of the energy supplied from the electric energy storage
section changes corresponding to a function of the predetermined
time period and the value relating to the voltage.
16. An electrotherapy apparatus according to claim 15, wherein the
value relating to the voltage is one of a voltage value, voltage
differential value, and voltage double differential value.
17. An electrotherapy apparatus according to claim 14, wherein the
control means controls the output in such a manner that the value
relating to the current which varies corresponding to the amount of
the energy supplied from the electric energy storage section
changes corresponding to a function of the predetermined time
period and the value relating to the current.
18. An electrotherapy apparatus according to claim 17, wherein the
value relating to the current is one of a current value, current
differential value, and current double differential value.
19. An electrotherapy apparatus according to claim 13, further
comprising: patient parameter measuring means for measuring the
patient parameter; output electrode parameter measuring means for
measuring the voltage generated between the output electrodes, or
the current flowing to the output electrode; and control means for
controlling the apparatus such that the electric power of the
electric energy becomes constant without depending on a value of
the patient impedance on the basis of the patient parameter
measured by the patient parameter measuring means before the second
phase waveform is outputted and a value, which relates to the
voltage between the output electrodes or the current flowing to the
output electrode, measured by the output electrode parameter
measuring means during the output of the second phase waveform.
20. An electrotherapy apparatus comprising: an electric energy
storage section generating a stimulation pulse; an output electrode
for applying the stimulation pulse to a patient; and control means
for controlling the shape of the waveform of the stimulation pulse
in such a manner that the predetermined electric energy stored in
the electric energy storage section is outputted to the output
electrode through an electric circuit within a predetermined time
period, wherein the electric circuit has a switch to control the
shape of the waveform of the stimulation pulse, and the control
means makes the switch conduct the continuous switching operation
by the pulse width modulation control during a period in which the
stimulation pulse is applied to the patient.
21. An electrotherapy apparatus according to claim 20, wherein the
control means has a reference curve to form the shape of the
waveform of the stimulation pulse into the predetermined shape.
22. An electrotherapy apparatus according to claim 21, wherein the
control means controls the switching operation of the switch on the
basis of the difference between the reference curve and the value
relating to the voltage which is lowered corresponding to the
amount of energy supplied from the energy storage section.
23. An electrotherapy apparatus according to claim 21, wherein the
control means controls the switching operation of the switch
according to the difference between the reference curve and the
value relating to the current which varies corresponding to the
amount of energy supplied from the energy storage section.
24. An electrotherapy apparatus according to claim 20, wherein the
control means controls so that the electric power of the electric
energy applied from the output electrode becomes constant without
depending on the value of the impedance of the patient.
25. An electrotherapy apparatus according to claim 21, further
comprising: patient parameter measuring means for measuring the
patient parameter; and output electrode parameter measuring means
for measuring the voltage generated between the output electrodes
or the current flowing to the output electrode, and wherein control
means controls the switching operation of the switch on the basis
of the patient parameter measured before the stimulation pulse is
outputted by the patient parameter measuring means and a value,
relating to the voltage between output electrodes or the current
flowing to the output electrode, measured during the output of the
stimulation pulse by the output electrode parameter measuring
means.
26. An electrotherapy apparatus according to claim 25, wherein the
control means controls in such a manner that the electric power of
the electric energy applied from the output electrode becomes
constant.
27. An electrotherapy apparatus comprising: an inductor section for
storing magnetic energy to generate a stimulation pulse; an output
electrode for applying the stimulation pulse to a patient; and
control means for controlling the shape of the waveform of the
stimulation pulse in such a manner that a predetermined energy in
the energy stored in the inductor section is delivered to the
patient through the output electrode.
28. An electrotherapy apparatus according to claim 27, wherein the
apparatus has an electric energy storage section to store the
energy in order to supply the energy to the inductor section.
29. An electrotherapy apparatus according to claim 28, wherein the
energy storage section is a capacitor, and when the energy stored
in the inductor section is supplied to the output electrode, the
control means can control in such a manner that the absolute value
of the output is higher than the absolute value of the voltage
stored in the capacitor.
30. An electrotherapy apparatus according to claim 28, wherein the
inductor section is connected to the electric energy storage
section through first switch means which is repeatedly switchable,
and the control means controls the repeated switching of the first
switch means.
31. An electrotherapy apparatus according to claim 30, wherein the
control means controls the switching of the first switch means by a
pulse width modulation control.
32. An electrotherapy apparatus according to claim 27, wherein the
control means controls the shape of the waveform of the stimulation
pulse in such manner that the electric power of the electric energy
applied from the output electrode becomes constant without
depending on the value of the impedance of the patient.
33. An electrotherapy apparatus according to claim 27, wherein the
control means has a reference curve in order to form the shape of
waveform of the stimulation pulse into the predetermined shape.
34. An electrotherapy apparatus according to claim 33, wherein the
control means controls the switching operation of the switch
according to the difference between the reference curve and the
value relating to the voltage which is lowered corresponding to the
amount of energy supplied from the energy storage section.
35. An electrotherapy apparatus according to claim 33, wherein the
control means controls the switching operation of the switch on the
basis of the difference between the reference curve and the value
relating to the current which varies corresponding to the amount of
energy supplied from the energy storage section.
36. An electrotherapy apparatus according to claim 2, further
comprising: a charging circuit for charging the energy storage
section.
37. An electrotherapy apparatus comprising: a positive polarity of
an electric energy storage section (104) connected to an inductor
(105) through first switch means (101), and from the opposite side
terminal of the inductor (105), connected to the negative polarity
of the electric energy storage section (104) through third switch
means (103); the opposite side terminal of the inductor (105)
connected to an output electrode (112a) to apply an electric pulse
on a patient (113) through an inductor (110); and an output
electrode (112b) connected to the negative polarity of the electric
energy storage section (104); and a diode (108) and a diode (109)
connected in series between the first switch means (101) and the
inductor (110), in which the inductor (110) side is an anode, and
the first switch means (101) side is a cathode; and a capacitor
(106) and a resistor (107) inserted between the diode (108) and the
diode (109), and between the inductor (105) and a switch (102); and
a protective resistor (111) inserted between the output electrode
(112a) and the output electrode (112b); and a charging circuit
(115) to charge the electric energy storage section (104); and in
which a diode (117) and a diode (118) are respectively inserted
between both polarities of the energy storage section (104) and the
charging circuit (115); a voltage monitoring circuit (114)
connected across both polarities of the energy storage section
(104); and a drive circuit (119) to control the open/close
operation of the first switch means (101); a drive circuit (120) to
control the open/close operation of second switch means (102); and
a drive circuit (121) to control the open/close operation of the
third switch means (103); and the drive circuit (119), the drive
circuit (120), the drive circuit (121) and the charging circuit
(115) structured so that these can be controlled by a
microprocessor (116).
38. An electrotherapy apparatus as claimed in claim 37, further
comprising: a current monitoring circuit (131) inserted between the
positive polarity of the electric energy storage section (104) and
the first switch means (101); a resistor (132) inserted such that
the resistor connects a portion between the current monitoring
circuit (131) and the first switch means (101) to a portion between
the inductor (105) and the second switch means (102); and the
microprocessor (116) at least has a ROM (141) in which the data of
the reference curve is previously stored, and a digital/analog
conversion circuit (140) to convert the data of the ROM (141) into
the analog data; a gain switching circuit (133), and a pulse width
modulation circuit (143) housing therein at least an error
amplifier (142); a pulse width modulation circuit (143) connected
such that a voltage signal (138) from the digital/analog conversion
circuit (140) and a voltage signal (137) from a gain switching
circuit (133) are inputted thereto; and the gain switching circuit
(133) connected such that a control signal (136) from the
microprocessor (116), a signal (135) from the current monitoring
circuit (131), and a signal (134) from the voltage monitoring
circuit (114) are inputted thereto.
39. An electrotherapy apparatus according to claim 2, wherein the
apparatus is applied to an external type which applies the
stimulation pulse onto the body surface of the patient.
40. An electric energy delivering method of the electrotherapy
apparatus when the electric energy stored in the electric energy
storage section is delivered to a patient in biphasic waveform
comprising: delivering a necessary electric energy in a first phase
waveform; delivering the necessary electric energy within a
predetermined time period from the remaining energy in a second
phase waveform.
41. An electric energy delivering method of the electrotherapy
apparatus according to claim 40, wherein the electric energy stored
in the electric energy storage section is delivered to the patient
in the first phase waveform and the second phase waveform by
alternately repeating a plurality of times, and is formed into a
multiphase output waveform.
Description
BACKGROUND OF INVENTION
[0001] 1. Field of Invention
[0002] The present invention relates to an internal and external
electrotherapy apparatus to apply an electric stimulation pulse
onto the patient and its electric energy delivering method, and
specifically to an electrotherapy apparatus effective in
terminating the fibrillation of hearts in cardiac diseases, and its
electric energy delivering method.
[0003] 2. Related Art
[0004] In patients having cardiac diseases, the fibrillation is an
important factor which causes the patient' death. In order to
terminate the fibrillation, an electrotherapy apparatus (called
defibrillator) which applies a shock by an electric stimulation
pulse (called defibrillation pulse) onto the heart of the patient
and terminates the fibrillation, is commonly used.
[0005] The internal defibrillator is adjusted and used for only an
individual patient, therefore, because the impedance between
electrodes is a value inherent to the patient and almost constant,
the waveform can be adjusted so that the defibrillation efficiency
becomes optimum for the impedance of the patient. On the other
hand, in the external defibrillator, the higher current output than
that of the internal type is necessary, and further, because the
impedance is used for various unspecified patients, when the
fibrillation is not terminated by the first electric shock, a
method of delivering shock again with the increased energy value is
applied.
[0006] Further, as the waveform, there are a monophasic type and a
biphasic type, and recently, the biphasic type in the both is known
to have advantages that the output electric energy may be smaller
than that of the monophasic type, the energy efficiency is high,
and the damage to the patient is small.
[0007] Referring to the drawing, an output circuit of the
conventional biphasic defibrillator will be described below. FIG.
10 is a view for explaining the output circuit of the conventional
biphasic defibrillator, and FIG. 11 is a view of its waveform.
[0008] FIG. 10(a) is an example in which a mechanism to reverse the
phase by four switches is provided, and the mechanism has a
capacitor 201 to store the electric energy, switches 202, 203, 204,
and 205, and output electrodes 206a, and 206b. This is the
technology disclosed in U.S. Pat. No. 4,850,357 (JP-B-4-45193).
[0009] In this biphasic defibrillator, when the first phase
(positive phase) waveform electric pulse is outputted, the switches
202 and 205 are turned on, and switches 203 and 204 are turned off,
and thereby, the positive polarity voltage of the capacitor 201 is
applied on the output electrode 206a, and the negative polarity
voltage of the capacitor 201 is applied on the output electrode
206b, and from these electrodes, the positive phase truncated
exponential waveform electric pulse is applied to the patient 207
(impedance of the patient: 207a). Then, when the voltage or time
comes to a predetermined value, the switches 202 and 205 are turned
off.
[0010] Next, in the case where the second phase (negative phase)
waveform electric pulse is outputted, when the switches 203 and 204
are turned on, the negative polarity voltage of the capacitor 201
is applied onto the output electrode 206a, and the positive
polarity voltage of the capacitor 201 is applied onto the output
electrode 206b, and from these electrodes, the negative phase
truncated exponential waveform electric pulse is applied onto the
patient 207. Then, when the voltage or time comes to a
predetermined value, the switches 203 and 204 are turned off.
[0011] According to that, from the output circuit of the above
conventional biphasic defibrillator, the truncated exponential
biphasic waveform as shown in FIG. 11(a) can be obtained.
[0012] Further, FIG. 10(b) is an example in which a mechanism to
reverse the phase by 2 capacitors is provided, and the mechanism
has capacitors 211 and 212 to store the electric energy, switches
213 and 214, and output electrodes 215a and 215b. This is a
technology disclosed in the U.S. Pat. No. 5,871,505.
[0013] In the biphasic defibrillator, in the case where the first
phase (positive phase) waveform electric pulse is outputted, when
the switch 213 is turned on, and the switch 214 is turned off, the
positive polarity voltage of the capacitor 211 is applied onto the
output electrode 215a, and the negative polarity voltage of the
capacitor 211 is applied onto the output electrode 215b, and from
these electrodes, the first phase (positive phase) truncated
exponential waveform electric pulse is applied onto the patient 216
(the impedance of the patient: 216a).
[0014] Then, when the voltage or time comes to a predetermined
value, the switch 213 is turned off.
[0015] Next, when the second phase (negative phase) waveform
electric pulse is outputted, the switch 214 is turned on, and the
switch 213 is turned off, thereby, the negative polarity voltage of
the capacitor 212 is applied onto the output electrode 215a, and
the positive polarity voltage of the capacitor 212 is applied onto
the output electrode 215b, and from these electrodes, the second
phase (negative phase) waveform electric pulse is applied onto the
patient 216.
[0016] It According to that, the biphasic waveform as shown in FIG.
11(b) is obtained from the output circuit of the above conventional
biphasic defibrillator.
[0017] A publicly known example disclosed in the U.S. Pat. No.
5,591,209 is for the implantable defibrillator, and a method in
which the first phase applies the energy stored inhigh voltage
storage capacitors onto the heart, and the second phase directly
applies the energy from the battery source in low voltage onto the
heart, is shown.
[0018] In the technology of the implantable defibrillator having
the low output energy disclosed in the U.S. Pat. No. 5,350,403
(JP-A-6-47100), a control unit is provided between a charging
capacitor and the electrode, and by turning on or off the circuit,
the electric pulse having a predetermined current curve is applied
onto the patient.
[0019] The U.S. Pat. No. 5,607,454 (JP-A-9-500309) uses the
truncated exponential curve. With this method, the durations of the
waveforms of the first phase and the second phase are changed
depending on the impedance of the patient.
[0020] Comparing to the monophasic defibrillator, the conventional
biphasic type defibrillator, for example, in the case of FIG.
10(a), 4 switches are necessary, and further, in the case of FIG.
10(b), 2 electric energy storage section (capacitor) are necessary,
and the number of elements is increased as compared to the
monophasic defibrillator.
[0021] Generally, in the defibrillator, in order to generate the
high voltage from the low voltage power source such as a battery,
even when the number of the electric energy storage sections
(capacitor) and switches (structured by superimposing a plurality
of stages of semiconductor switches) is increased by, for example,
only one, the apparatus becomes larger and heavier, therefore,
problems that the portability in the emergency circumstances is
lowered, or the like, are caused, and further, the cost of the
overall apparatus is also increased.
[0022] In the output system of the conventional truncated
exponential waveform as disclosed in the U.S. Pat. No. 5,607,454
(JP-W-9-500309), the impedance of the patient directly influences
the decay of the voltage of the capacitor, and the time constant is
unconditionally determined, and as the control to form the
waveform, it can operate only when the waveform output is completed
(truncated).
[0023] Further, in the external defibrillator, because the electric
stimulation pulse is applied transthoracically, the impedance
applied across output electrodes during operation is different
depending on the patient (inherency), and further, the large
difference is generated depending on the physical and physiological
difference of the patient.
[0024] Further, in the following references 1 and 2, when the time
period in which the electric pulse is applied, is not within a
predetermined time period, the effective defibrillation can not be
carried out.
[0025] Reference 1: Koning G. Schneider H. Hoelin AJ. et al.
"Amplitude-duration relation for direct ventricular defibrillation
with rectangular pulses." Medical & Biological Engineering, May
1975: on page 388-395.
[0026] Reference 2: "Ventricular Defibrillation Using Biphasic
Waveforms: The Importance of Phasic Duration" JACC January 1989
13:1 207-14.
[0027] Accordingly, when the sufficient electric energy can not be
delivered within this effective period, even when the electric
pulse is continuously applied over this period, there is a problem
that the effect of the defibrillation can not be increased.
[0028] Accordingly, when the impedance of the patient is high,
because only by the output of the conventional truncated
exponential waveform, it takes a lot of time to deliver the
electric energy to the patient, the sufficient energy can not be
delivered within the effective period to apply the defibrillation
pulse, and therefore it unavoidably truncates the output of the
defibrillation pulse.
[0029] Further, in the technology disclosed in the U.S. Pat. No.
5,591,209, the energy stored in the high voltage storage capacitors
is used only for the first phase waveform. Accordingly, all the
energy stored in the capacitors is not used for the
defibrillation.
[0030] That is, in such the waveform, because the first phase is
completed under the condition that the voltage of the capacitors is
lowered to about 40%, it comes to an account that about 16% of
overall amount of the energy stored in the capacitors are not used
for the defibrillation.
[0031] In the external defibrillator, normally, it is necessary
that the safety is secured by electrically isolating the circuit
passing through the low voltage power source and the patient, (for
example, some measures to isolate the patient at the time of the
second phase output is provided), however, it is not disclosed in
the above publicly known examples.
[0032] Further, when the technology in the above publicly known
examples is applied for the external defibrillator, it is
additionally necessary to provide the insulation circuit composed
of transformer, or the like, to output the second phase other than
the insulation transformer to store the energy in the energy
storage section, and it is not preferable from the viewpoint of the
size reduction to apply it for the external type.
[0033] Further, because it is the system that the power source of
the second phase is directly applied from the power source
apparatus (battery source), the instantaneous maximum electric
power applied on the patient is limited by the maximum electric
power of the power source apparatus.
[0034] When such the system is applied for the external
defibrillator, because the very large instantaneous electric power
is required as compared to that of the internal defibrillator, when
the capacity of the power source is not designed to be large, the
effective defibrillation pulse can not be outputted. Generally, the
inherency of the impedance value of the patient spreads to the
range from 25 .OMEGA. to 125 .OMEGA..
[0035] For example, in the second phase, in order to apply the
voltage of 300 V to the patient, the power source capacity P shown
by the following equation 1 is required.
P=300 (V).sup.2/25(.OMEGA.)=3600 (Watt) (1)
[0036] As described above, because the very large power source
capacity of 3600 (Watt) is necessary, it is difficult also from the
viewpoint of the power source capacity to apply for the external
defibrillation.
[0037] Further, because the power is not controlled in the second
phase, the necessary energy can not always be delivered within the
effective time period.
[0038] Further, in the technology disclosed in the U.S. Pat. No.
5,350,403 (JP-A-6-47100), the control unit which can turn on or
turn off the circuit, is provided between the charging capacitor
and electrode, and the maximum voltage value of the output waveform
obtained at the time of the control can not be larger than the
capacitor voltage obtained when the circuit is continuously turned
on by the control unit.
[0039] This is for the reason why the unit is structured such that
the control unit is operated only in the direction to control the
output.
[0040] Further, at the time of the defibrillation, when the
impedance of the patient is large, there is a case in which it is
preferable that the higher voltage than the voltage stored in the
charging capacitor is supplied to the patient. In the conventional
technology, in order to defibrillate in biphasic waveform, it is
necessary that the 2 charging capacitors are additionally prepared,
and the reverse of the polarity of the output voltage is conducted
by using 4 switches (called H-bridge).
SUMMARY OF INVENTION
[0041] The present invention is attained in view of problems of the
conventional technologies, and an object of the present invention
is to solve the above problems, and to provide the electrotherapy
apparatus which is effective in terminating the fibrillation of the
heart in cardiac diseases, and its electric energy delivering
method.
[0042] In order to solve the above problems, the electrotherapy
apparatus according to the first aspect of the invention, has the
electric energy storage section to generate the stimulation pulse,
and the output electrode to apply the stimulation pulse to the
patient, and is structured so that the polarity of the voltage
outputted to the output electrode is reversed, and is structured
such that at least the first phase waveform and the second phase
waveform of the electric energy are outputted from the output
electrode, and the shape of the second phase waveform of the
electric energy can be controlled, thereby, the output waveform of
the second phase can be freely set, without depending on the
voltage (V1t) of the electric energy storage section at the time of
the start of the second phase.
[0043] The electrotherapy apparatus according to the second aspect
of the invention, has the electric energy storage section to
generate the stimulation pulse, and the output electrode to apply
the stimulation pulse to the patient, and is structured so that the
polarity of the voltage outputted to the output electrode is
reversed, and is structured such that at least the first phase
waveform and the second phase waveform are outputted from the
output electrode, and the necessary electric energy is delivered
within a predetermined time period by the outputted second phase
waveform of the electric energy, thereby, the predetermined
electric energy can be delivered to the patient within an optimum
time period for the defibrillation, without depending on the
impedance of the patient.
[0044] The electrotherapy apparatus according to the third to
seventh aspect of the invention, has a control means for
controlling so that the electric power of the electric energy
outputted from the output electrode becomes a predetermined value,
without depending on the impedance of the patient, during the
output period of the second phase waveform.
[0045] Further, the control means output controls so that the value
relating to the voltage which is lowered corresponding to the
amount of the energy supplied from the electric energy storage
section, varies corresponding to the function of the predetermined
time period and the value relating to the voltage.
[0046] The value relating to the voltage is the voltage, the
voltage differential value, or voltage double differential
value.
[0047] The control means output controls so that the value relating
to the current which varies corresponding to the amount of the
energy supplied from the electric energy storage section, changes
corresponding to the function of the predetermined time period and
the value relating to the current.
[0048] The value relating to the current is the current, the
current differential value, or current double differential
value.
[0049] As described above, by controlling the electric parameters
relating to the energy storage section which are varied
corresponding to the amount of the delivery of the electric energy,
the delivering energy can be controlled.
[0050] The electrotherapy apparatus according to the eighth aspect
of the invention has: a patient parameter measuring means for
measuring the patient parameter; an output electrode parameter
measuring means for measuring the voltage generated between the
output electrodes or the current flowing to the output electrode;
and a control means for controlling so that the electric power of
the electric energy becomes a predetermined value without depending
on the values of the patient parameters, according to the patient
parameters measured before the output of the second phase waveform
by the patient parameter measuring means, and to the value relating
to the voltage between the output electrodes or the value relating
to the current flowing to the output electrode, measured during the
output of the second phase waveform, by the output electrode
parameter measuring means, thereby, the electric power of the
output energy can be controlled according to the patient parameter
before the output of the second phase waveform, and the electric
parameter on the output electrode during the output of the second
phase waveform.
[0051] The electrotherapy apparatus according to the ninth aspect
of the invention is structured such that: when the waveform of the
electric energy outputted from the output electrode is the first
phase waveform, the inductor, electric energy storage section, the
first switch means, output electrode, patient and at least the
other output electrode are connected so that these can form the
closed circuit; and in the case where the waveform of the electric
energy outputted from the output electrode is the second phase,
when the first switch means is closed, the inductor and the
electric energy storage section form the closed circuit in the
apparatus not including the patient, and when the first switch
means is opened, the inductor and the electric energy storage
section are electrically separated from each other, and the
electric energy to the output electrode is delivered from the
inductor, thereby, the biphasic defibrillator (electrotherapy
apparatus) can be structured by one electric energy storage
section, and the second phase output waveform can be freely
set.
[0052] The electrotherapy apparatus according to the tenth aspect
of the invention is structured such that the shape of the second
phase waveform can be controlled by the open/close of the first
switch means, thereby, when only one switch means is opened and
closed, the second phase output waveform can be freely set by the
simple control method.
[0053] The electrotherapy apparatus according to the eleventh
aspect of the invention has the second switch means and the third
switch means to shape the first phase and the second phase of the
waveform of the electric energy outputted from the output
electrode, thereby, when only two switch means are opened and
closed, the first phase and the second phase can be formed by the
simple control means.
[0054] In the electrotherapy apparatus according to the twelfth
aspect of the invention, the first switch means, the second switch
means, and the third switch means are structured by the
semiconductor switches, thereby, the opening and closing of each
switch means can be conducted with high speed by the electric
control.
[0055] The electrotherapy apparatus according to the thirteenth
aspect of the invention has: the electric energy storage section to
generate the stimulation pulse; the output electrode to apply the
stimulation pulse to the patient; and the control means for
controlling the waveform shape of the stimulation pulse so that the
predetermined electric energy stored in the electric energy storage
section is outputted to the output electrode through the electric
circuit within a predetermined time period, thereby, by controlling
the shape of the pulse waveform, the apparatus is structured so
that the necessary energy can be outputted within a constant time
period, thereby the effective energy can be delivered in an
effective stimulation period.
[0056] In the electrotherapy apparatus according to the fourteenth
aspect of the invention, when the control means controls the
waveform shape of the stimulation pulse so that the electric power
of the electric energy applied from the electrode becomes a
predetermined value, without depending on the value of the
impedance of the patient, the electric power is controlled so that
it becomes a predetermined value without depending on the value of
the impedance even when the impedance of the patient is low or
high, thereby, the stimulation pulse having the effective energy
amount can be applied within a predetermined time period.
[0057] In the electrotherapy apparatus according to the fifteenth
to eighteen aspect of the invention, the control means output
controls so that the value relating to the voltage which is lowered
corresponding to the amount of the energy supplied from the
electric energy storage section, changes corresponding to the
function of the predetermined time and the value relating to the
voltage.
[0058] Further, the value relating to the voltage is the voltage
value, the voltage differential value, or the voltage double
differential value.
[0059] The control means output controls so that the value relating
to the current which varies corresponding to the amount of the
energy supplied from the electric energy storage section, changes
corresponding to the function of the predetermined time and the
value relating to the current.
[0060] The value relating to the current is the current value, the
current differential value, or the current double differential
value.
[0061] According to the above, the delivering energy can be
controlled by controlling the electric parameters relating to the
energy storage section which are changed corresponding to the
energy delivering amount.
[0062] The electrotherapy apparatus according to the ninteenth
aspect of the invention has: a patient parameter measuring means
for measuring the patient parameter; and an output electrode
parameter measuring means for measuring the voltage generated
across the output electrodes or the current flowing to the output
electrode, and the control means controls so that the electric
power of the electric energy becomes a predetermined value without
depending on the values of the patient impedance, according to the
patient parameters measured before the output of the second phase
waveform by the patient parameter measuring means, and to the value
relating to the voltage between the output electrodes or the value
relating to the current flowing to the output electrode, measured
during the output of the second phase waveform, by the output
electrode parameter measuring means, thereby, the electric power of
the output energy can be controlled according to the patient
parameter before the output of the second phase waveform, and the
electric parameter on the output electrode during the output of the
second phase waveform.
[0063] The electrotherapy apparatus according to the twentieth
aspect of the invention has: the electric energy storage section to
generate the stimulation pulse; the output electrode to apply the
stimulation pulse to the patient; and the control means for
controlling the waveform shape of the stimulation pulse so that the
predetermined electric energy stored in the electric energy storage
section is outputted to the output electrode through the electric
circuit within a predetermined time period, and the electric
circuit has the switch to control the waveform shape of the
stimulation pulse, and the control means operates the switch to
conduct the continuous switching operation by the pulse width
modulation control during a period in which the stimulation pulse
is applied to the patient, thereby, by operating the switch in the
electric circuit to continuously conduct the switching operation by
the pulse width modulation system, the electric power can be
controlled so that the necessary energy is delivered.
[0064] In the electrotherapy apparatus according to the twenty
first aspect of the invention, the control means has the reference
curve so that the waveform shape of the stimulation pulse is formed
into the predetermined shape, thereby, by controlling according to
the reference curve stored in the control means, the stimulation
pulse having the predetermined shape can be applied.
[0065] In the electrotherapy apparatus according to the twenty
second to the twenty third aspect of the invention, the control
means controls the switching operation of the switch according to
the difference between the value relating to the voltage which is
lowered corresponding to the amount of the energy supplied from the
electric energy storage section, and the reference curve, or the
control means controls the switching operation of the switch
according to the difference between the value relating to the
current which varies corresponding to the amount of the energy
supplied from the electric energy storage section, and the
reference curve, thereby, by controlling the electric parameters
relating to the energy storage section which varies corresponding
to the amount of the supplied energy, according to the reference
curve, the delivering energy can be controlled.
[0066] In the electrotherapy apparatus according to the twenty
fourth aspect of the invention, the control means controls so that
the electric power of the electric energy outputted from the output
electrode becomes a predetermined value, without depending on the
impedance of the patient, thereby, even when the impedance of the
patient is low or high, by controlling so that the electric power
becomes a predetermined value, without depending on the impedance
value, the stimulation pulse having the effective amount of the
energy can be applied.
[0067] The electrotherapy apparatus according to the twenty fifth
aspect of the invention has: a patient parameter measuring means
for measuring the patient parameter; an output electrode parameter
measuring means for measuring the voltage generated between the
output electrodes or the current flowing to the output electrode,
and a control means controls the switching operation of the switch,
according to the patient parameters measured before the output of
the stimulation pulse by the patient parameter measuring means, and
to the value relating to the voltage between the output electrodes
or the value relating to the current flowing to the output
electrode, measured during the output of the stimulation pulse, by
the output electrode parameter measuring means, thereby, the
electric power of the energy can be controlled according to the
patient parameter before the output of the stimulation pulse and
the electric parameter on the output electrode during the applying
of the stimulation pulse.
[0068] In the electrotherapy apparatus according to the twenty
sixth aspect of the invention, the control means controls so that
the electric power of the electric energy applied from the output
electrode becomes a predetermined value, thereby, even when the
impedance of the patient is low or high, by controlling so that the
electric power becomes a predetermined value, without depending on
the impedance value, the stimulation pulse having the effective
amount of the energy can be applied.
[0069] The electrotherapy apparatus according to the twenty seventh
aspect of the invention has: an inductor section to store the
magnetic energy to generate the stimulation pulse; the output
electrode to apply the stimulation pulse to the patient; and the
control means for controlling the waveform shape of the stimulation
pulse so that the predetermined energy in the energy stored in the
inductor section is delivered to the patient through the output
electrode, thereby, because the apparatus is structured such that
the electric energy is supplied to the inductor, the waveform shape
of the stimulation pulse can be controlled with the high degree of
freedom.
[0070] The electrotherapy apparatus according to the twenty eighth
aspect of the invention has, in order to supply the energy to the
inductor section, the electric energy storage section to store the
energy, thereby, because the apparatus has the electric energy
storage section to store the electric energy other than the
inductor, a predetermined amount of the energy in the energy stored
in the electric energy storage section can be supplied to the
inductor.
[0071] In the electrotherapy apparatus according to the twenty
ninth aspect of the invention, the electric energy storage section
is a capacitor, and when the energy stored in the inductor section
is supplied to the output electrode, the control means can control
so that the absolute value of the output is higher than the
absolute value of the voltage stored in the capacitor, thereby,
because the control means controls so that the energy is supplied
by the inductor, even when the patient has the high impedance, the
energy can be supplied while the voltage value outputted to the
output electrode is increased higher than that of the capacitor at
need, which is the electric energy storage section.
[0072] In the electrotherapy apparatus according to the thirtieth
aspect of the invention, the inductor section is connected to the
electric energy storage section through the first switch means
which can be repeatedly switched, and the control means conducts
the switching control by controlling the repeated switching of the
first switch means, thereby, the energy stored in the capacitor is
supplied once to the inductor, and it can be supplied to the output
electrode.
[0073] In the electrotherapy apparatus according to the thirty
first aspect of the invention, the control means controls the
switching of the first switch means by the pulse width modulation
control, thereby, the electric power can be controlled.
[0074] In the electrotherapy apparatus according to the thirty
second aspect of the invention, in the electrotherapy apparatus,
the control means controls the waveform shape of the stimulation
pulse so that the electric power of the electric energy outputted
from the output electrode becomes constant without depending on the
impedance of the patient, thereby, even when the impedance of the
patient is low or high, by controlling so that the electric power
becomes constant without depending on the impedance value, the
stimulation pulse having the effective energy amount can be
applied.
[0075] In the electrotherapy apparatus according to the thirty
third aspect of the invention, the control means stores the
reference curve in order to form the waveform shape of the
stimulation pulse into the predetermined shape, thereby, by
controlling according to the stored reference curve, the
stimulation pulse having the predetermined shape can be
applied.
[0076] In the electrotherapy apparatus according to the thirty
fourth to thirty fifth aspect of the invention, the control means
controls the switching operation of the switch according to the
difference between the value relating to the voltage which is
lowered corresponding to the energy amount supplied from the
electric energy storage section, and the reference curve, and
further, the control means controls the switching operation of the
switch according to the difference between the value relating to
the current which varies corresponding to the energy amount
supplied from the electric energy storage section, and the
reference curve, thereby, by controlling the electric parameters
relating to the energy storage section which varies corresponding
to the energy supply amount according to the reference curve, the
supply energy can be controlled.
[0077] The electrotherapy apparatus according to the thirty sixth
aspect of the invention has a charging circuit to charge the
electric energy storage section, thereby, when the energy is
consumed by the use, the apparatus can be used again.
[0078] In the electrotherapy apparatus according to the thirty
seventh aspect of the invention, the positive polarity of the
electric energy storage section is connected to the inductor
through the first switch means, and from the opposite side terminal
of the inductor, through the third switch means, is connected to
the negative polarity of the electric energy storage section; the
opposite side terminal of the inductor is connected to the output
electrode to apply the electric pulse onto the patient through the
second switch means and the inductor; and the output electrode is
connected to the negative polarity of the electric energy storage
section; to a portion between the first switch means and the
inductor, two diodes are connected in series, in which the inductor
side is the anode, and the first switch means side is the cathode;
the capacitor and the resistor are inserted between a portion
between the two diodes, and a portion between the inductor and the
switch; the protective resistor is inserted between the output
electrodes; and the apparatus has the charging circuit to charge
the electric energy storage section; the two diodes are
respectively inserted between both polarities of the electric
energy storage section and the charging circuit; the voltage
monitoring circuit is connected to both polarities of the electric
energy storage section; the apparatus has the drive circuit to
control the open/close operation of the first switch means, the
drive circuit to control the open/close operation of the second
switch means, and the drive circuit to control the open/close
operation of the third switch means; and the three drive circuits
and the charging circuit are structured so that these can be
controlled by the microprocessor, thereby, the biphasic electric
stimulation pulse waveform can be freely outputted, and the
conventional problems are solved, and it is effective in
terminating the fibrillation of the heart in the cardiac
diseases.
[0079] In the electrotherapy apparatus according to the thirty
eighth aspect of the invention, the positive polarity of the
electric energy storage section is connected to the inductor
through the first switch means, and from the opposite side terminal
of the inductor, through the third switch means, is connected to
the negative polarity of the electric energy storage section; the
opposite side terminal of the inductor is connected to the output
electrode to apply the electric pulse onto the patient through the
second switch means and the inductor; and the output electrode is
connected to the negative polarity of the electric energy storage
section; to a portion between the first switch means and the
inductor, the two diodes are connected in series, in which the
inductor side is the anode, and the first switch means side is the
cathode; the capacitor and the resistor are inserted between a
portion between two diodes, and a portion between the inductor and
the switch; the protective resistor is inserted between the output
electrodes; and the apparatus has the charging circuit to charge
the electric energy storage section; the two diodes are
respectively inserted between both polarities of the electric
energy storage section and the charging circuit; the voltage
monitoring circuit is connected to both electrodes of the electric
energy storage section; the apparatus has the drive circuit to
control the open/close operation of the first switch means, the
drive circuit to control the open/close operation of the second
switch means, and the drive circuit to control the open/close
operation of the third switch means; and the three drive circuits
and the charging circuit are structured so that these can be
controlled by the microprocessor; the current monitoring circuit is
inserted between the positive polarity of the electric energy
storage section and the first switch means; the resistor is
inserted so that a portion between the current monitoring circuit
and the first switch means, and a portion between the inductor and
the second switch means are connected; the microprocessor at least
has the ROM in which the data of the reference curve is previously
stored, and the digital/analog conversion circuit to convert the
data of the ROM to the analog data, the gain switching circuit, the
pulse width modulation circuit in which at least the error
amplifier is housed; the pulse width modulation circuit is
connected so that the voltage signal from the digital/analog
conversion circuit and the voltage signal from the gain switching
circuit are inputted; the gain switching circuit is connected so
that the control signal from the microprocessor, the signal from
the current monitoring circuit, and the signal from the voltage
monitoring circuit are inputted; thereby, the biphasic electric
stimulation pulse waveform can be freely outputted, and the
conventional problems are solved, and it is effective in
terminating the fibrillation of the heart in the cardiac
diseases.
[0080] The electrotherapy apparatus according to the thirty ninth
aspect of the invention is the external type by which the
stimulation pulse is applied onto the body surface of the patient,
thereby, the same apparatus can be used for the other patient.
[0081] The electric energy delivering method of the electrotherapy
apparatus according to the fortieth aspect of the invention is a
method by which, the electric energy stored in the electric energy
storage section is delivered to the patient in biphasic waveform,
initially, the necessary electric energy is delivered in the first
phase waveform, and next, the necessary electric energy, from the
remained energy, is delivered in the second phase waveform within a
predetermined time period, thereby, the second phase waveform
having a predetermined electric energy can be applied to the
patient within the optimum time period for the defibrillation,
without depending on the impedance of the patient.
[0082] In the electric energy delivering method of the
electrotherapy apparatus according to the forty first aspect of the
invention, the electric energy stored in the electric energy
storage section, is repeatedly delivered onto the patient in the
first phase waveform and the second phase waveform at the plurality
of times alternately (multiphasic output waveform), by freely
forming the shape of the second phase waveform without depending on
the impedance of the patient, there is a possibility that the more
effective defibrillation can be conducted.
BRIEF DESCRIPTION OF DRAWINGS
[0083] FIG. 1 is a block structural view showing an electrotherapy
apparatus according to the first embodiment of the present
invention.
[0084] FIG. 2 is a view explaining a current path when a positive
phase waveform is outputted.
[0085] FIGS. 3(a) and (b) are views explaining the current path
when the first switch means is turned on at the time of a negative
phase waveform output.
[0086] FIG. 4 is a view explaining the current path when the first
switch means is turned off at the time of the negative phase
waveform output.
[0087] FIG. 5 is a block structural view showing the electrotherapy
apparatus according to the second and third embodiments of the
present invention.
[0088] FIGS. 6(a) to (d) are views for explaining an output
waveform of the electrotherapy apparatus according to the first to
third embodiments of the present invention.
[0089] FIG. 7 is a block structural view showing the electrotherapy
apparatus according to the fourth to sixth embodiments of the
present invention.
[0090] FIGS. 8(a) and (b) are views showing an example of the
preferable reference curves of the voltage and current according to
the fourth to sixth embodiments of the present invention.
[0091] FIG. 9 is a view showing an example of the relationship
between the impedance of the patient and the output voltage
waveform according to the fourth to sixth embodiments of the
present invention.
[0092] FIGS. 10(a) and (b) are views for explaining the output
circuit of the conventional biphasic defibrillator.
[0093] FIGS. 11(a) and (b) are views for explaining the output
waveforms of the conventional biphasic defibrillator.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0094] Referring to the drawings, each embodiment of the
electrotherapy apparatus of the present invention will be detailed
below.
[0095] In each embodiment, the explanation is conducted as the
first phase waveform is the positive phase, and the second phase
waveform is the negative phase, however, it may be allowed that the
first phase waveform is the negative phase, and the second phase
waveform is the positive phase.
[0096] The First Embodiment
[0097] FIG. 1 is a block structural view showing the electrotherapy
apparatus according to the first embodiment of the present
invention.
[0098] As shown in FIG. 1, the electrotherapy apparatus 100 is
structured as follows.
[0099] A positive polarity of the electric energy storage section
104 using a capacitor and the like, is connected to an inductor 105
through a switch 101 (the first switch means), and further, the
opposite side terminal of the inductor 105 is connected to a
negative polarity of the electric energy storage section 104
through a switch 103 (the third switch means). Further, the
opposite side terminal of the inductor 105 is connected to the one
output electrode 112a to apply an electric stimulation pulse onto
the patient 113 (the impedance of the patient is 113a) through a
switch 102 (the second switch means), through the inductor 110.
[0100] Further, the other output electrode 112b is connected to the
negative polarity of the electric energy storage section 104.
[0101] A diode 108 and a diode 109 for reverse current prevention,
whose inductor 110 side is the anode, and the switch 101 side is
the cathode, are connected in series between the switch 101 and the
inductor 110, and between two diodes, that is, between the cathode
of the diode 109, and a portion between the inductor 105 and the
switch 102, a capacitor 106 and a resistor 107 to smooth the
waveform are inserted.
[0102] Further, a protective resistor 111 is inserted between the
output electrodes 112a and 112b.
[0103] Charging to the electric energy storage section 104 is
conducted by a charging circuit 115.
[0104] Incidentally, a diode 117 and a diode 118 for reverse
current prevention are respectively inserted between both
polarities of the electric energy storage section 104 and the
charging circuit 115.
[0105] Further, a voltage monitoring circuit 114 is connected
between both polarities of the electric energy storage section 104,
and monitors the voltage stored in the electric energy storage
section 104, and a voltage signal 122 to transmit the detected
voltage is connected to a microprocessor 116.
[0106] Further, switches 101, 102, and 103 are connected so that
the control of their open/close operations is conducted by a drive
circuit 119 of the switch 101, drive circuit 120 of the switch 102,
and drive circuit 121 of the switch 103, and these drive circuits
119, 120, and 121 are controlled by the control signals 124, 125,
and 126 from a microprocessor 116. Further, the microprocessor 116
controls the charging circuit 115 by a control signal 123.
[0107] Incidentally, the switch 101 (the first switch means),
switch 102 (the second switch means), and switch 103 (the third
switch means) are preferably structured by semiconductor switches
consisting of insulated gate bipolar transistors (IGBT).
[0108] An output control method of the electric stimulation pulse
of the electrotherapy apparatus according to the first embodiment
will be described bellow.
[0109] Initially, the charging operation of the electric energy to
the electric energy storage section 104 will be described (step
1-1-1-7).
[0110] Step 1-1: A charge start command is inputted into the
microprocessor 116.
[0111] Step 1-2: The microprocessor 116 outputs the control signals
124, 125, 126 to the drive circuits 119, 120, 121 of each switch so
that the switches 101, 102, and 103 are in the continuous
turning-off status.
[0112] Step 1-3: Switches 101, 102 and 103 are in the continuous
turning-off status.
[0113] Step 1-4: The microprocessor 116 outputs the control signal
123 for the charging start to the charging circuit 115.
[0114] Step 1-5: The charging circuit 115 starts the energy
charging to the electric energy storage section 104.
[0115] Step 1-6: The microprocessor 116 receives the voltage signal
122 from the voltage monitoring circuit 114, and when the voltage
of the electric energy storage section 104 monitored by the voltage
monitoring circuit 114 rises to a predetermined value, the
microprocessor 116 outputs the control signal 123 for charging stop
to the charging circuit 115.
[0116] Step 1-7: The charging circuit 115 stops the energy charging
to the electric energy storage section 104.
[0117] Next, referring to FIG. 2, relating to the output operation
of the electric energy to the output electrodes 112a, 112b to apply
the electric stimulation pulse from the electric energy storage
section 104 onto the patient, the operation at the time of the
positive phase waveform output will be described (Step 1-8-Step
1-14). FIG. 2 is a view explaining the current path at the time of
the positive phase waveform output.
[0118] Step 1-8: According to the pressing of the discharge start
button (not shown) by the operator, the discharge start command is
inputted into the microprocessor 116.
[0119] Step 1-9: The microprocessor 116 outputs control signals
124, 125 and 126 to the drive circuits 119, 120 and 121 so that the
switch 101 and the switch 102 are in the continuous turning-on
status, and the switch 103 is in the continuous turning-off
status.
[0120] Step 1-10: The switch 101 and the switch 102 are in the
continuous turning-on status, and the switch 103 is in the
continuous turning-off status.
[0121] Step 1-11: The electric energy is delivered onto the patient
113 in the positive phase waveform. The voltage of the electric
energy storage section 104 is decreased.
[0122] Step 1-12: For example, when the voltage of the electric
energy storage section 104 is attenuated from the initial voltage
to a predetermined rate (for example, 37%), according to the
predetermined protocol, the microprocessor 116 outputs control
signals 124, 125 and 126 to the drive circuits 119, 120 and 121 so
that the switch 101 and the switch 102 are in the continuous
turning-off status, and the switch 103 is in the continuous
turning-on status.
[0123] Step 1-13: The switch 101 and the switch 102 are in the
continuous turning-off status, and the switch 103 is in the
continuous turning-on status.
[0124] Step 1-14: The electric energy output (positive phase
waveform output) to the patient 113 is completed.
[0125] Next, relating to the output operation of the electric
energy to the output electrodes 112a and 112b to apply the electric
stimulation pulse onto the patient 113 from the electric energy
storage section 104, the operation at the time of the negative
phase waveform output will be explained by using FIG. 3(a), FIG. 4
and FIG. 3(b) (Step 1-15-Step 1-20).
[0126] FIG. 3(a) is a view explaining the current path in the case
of the turning-on status of the switch 101 for the first time at
the time of the negative phase waveform output, FIG. 4 is a view
explaining the current path in the case of the turning-off status
of the switch 101 at the time of the negative phase waveform
output, and FIG. 3(b) is a view explaining the current path in the
case of the turning-on status of the switch 101 for the second and
the subsequent time at the time of the negative phase waveform
output.
[0127] As shown in FIG. 3(a), when the switch 101 (the first switch
means) is in the turning-on status for the first time at the time
of the negative phase waveform output, the current flows along the
current path 151 shown by an arrow. Then, the inductor 105 and the
capacitor 104 forms the closed circuit in the apparatus without
including the patient.
[0128] At this time, when the current flows though the current path
151, the electric energy in the electric energy storage section 104
is stored in the inductor 105 as the magnetic energy.
[0129] In this stage, the electric energy is not outputted to the
patient 113.
[0130] As shown in FIG. 4, when the switch 101 (the first switch
means) is in the turning-off status at the time of the negative
phase waveform output, the current flows along the current path 153
shown by an arrow.
[0131] In this case, the diodes 108 and 109 are in the turning-on
status, and the magnetic energy stored in the inductor 105 is
outputted as the electric energy, and the current flows along the
current path 153.
[0132] Accordingly, the electric energy is delivered to the patient
113.
[0133] Further, simultaneously the current flows into the capacitor
106, and the electric energy is stored in the capacitor 106.
[0134] As shown in FIG. 3(b), when the switch 101 (the first switch
means) is in the turning-on status for the second and the
subsequent time at the time of the negative phase waveform output,
the current flows along the arrowed current paths 151 and 152.
[0135] In this case, the diode 108 is in the turning-off status,
and the diode 109 maintains the turning-on status.
[0136] Accordingly, the electric energy stored in the capacitor 106
is outputted, and the current flows along the current path 152.
[0137] Accordingly, the status in which the electric energy is
delivered to the patient 113, is maintained.
[0138] Further, simultaneously, when the current flows through the
current path 151, the electric energy in the electric energy
storage section 104 is stored in the inductor 105 as the magnetic
energy. The operation at the time of the negative phase waveform
output will be explained as follows:
[0139] Step 1-15: The microprocessor 116 outputs the control signal
to control the turning-on/off of the switch 101 to the drive
circuit 119 of the switch 101 so that the desired output waveform
can be outputted, by using a previously set reference curve, that
will be explained later.
[0140] Step 1-16: The switch 101 conducts the switching operation
which repeats the turning-on/off. In the steps herein, by the
switching operation which repeats the turning-on/off of the switch
101, the conditions of the current paths follow from FIG. 3(a),
FIG. 4, to FIG. 3(b), and after that, the conditions of FIG. 4 and
FIG. 3(b) are repeated.
[0141] Step 1-17: The electric energy is delivered to the patient
113 in the negative phase waveform. The voltage in the electric
energy storage section 104 is decreased via the inductor 106 and
the capacitor 107.
[0142] Step 1-18: According to the predetermined protocol, in order
to end the energy output to the patient in the negative phase
waveform, the microprocessor 116 outputs the control signal 124 to
the drive circuit 119 so that the switch 101 is in the continuous
turning-off status.
[0143] Step 1-19: The switch 101 is in the continuous turning-off
status.
[0144] Step 1-20: The energy output (negative phase waveform
output) to the patient 113 is completed.
[0145] The Second Embodiment
[0146] FIG. 5 is a block structural view showing the electrotherapy
apparatus according to the second embodiment of the present
invention.
[0147] As shown in FIG. 5, this electrotherapy apparatus 130 is
structured as follows. Portions common to each portion in the above
described FIG. 1 are shown by the same numeral codes, and the
explanation is neglected.
[0148] In the electrotherapy apparatus according to the second
embodiment, the following structures are added to the
electrotherapy apparatus according to the first embodiment.
[0149] A current monitoring circuit 131 is inserted between the
positive polarity of the electric energy storage section 104 and
the switch 101, and further, a resistor 132 is inserted in such a
manner that a portion between the current monitoring circuit 131
and the switch 101, is connected to a portion between the inductor
105 and the switch 102.
[0150] Further, the microprocessor 116 has at least a ROM 141 in
which the data of the reference curve is previously stored, and a
digital/analog conversion circuit 140 to convert the ROM data into
the analog data.
[0151] Further, a gain switching circuit 133, and a pulse width
modulation circuit 143 in which the error amplifier 142 is housed
are provided, and the pulse width modulation circuit 143 is
connected so that the voltage signal 138 (the voltage of the
reference curve) from the digital/analog conversion circuit 140,
and the voltage signal 137 from the gain switching circuit 133 are
inputted.
[0152] Further, the gain switching circuit 133 is connected so that
the control signal 136 from the microprocessor 116, the signal 135
from the current monitoring circuit 131, and the signal 134 from
the voltage monitoring circuit 114 are inputted.
[0153] The electric energy delivering method of the electrotherapy
apparatus according to the present embodiment will be detailed
below.
[0154] This method is an electric energy delivering method to
output control so that the voltage which is lowered corresponding
to the energy amount outputted from the electric energy storage
section 104 is decreased corresponding to a function of the
predetermined time and voltage (Step 2-1-Step 2-15).
[0155] Step 2-1: The charging to the electric energy storage
section 104 is completed. At this time, switches 101, 102, and 103
are in the turning-off status.
[0156] Step 2-2: According to the pressing of the discharge start
button (not shown) by the operator, the discharge start command is
inputted into the microprocessor 116.
[0157] Step 2-3: The microprocessor 116 calculates the discharging
end voltage (V1t) of the first phase (positive phase) and the
discharging end voltage (V2t) of the second phase (negative phase)
from the voltage of the electric energy storage section 104 at this
time.
[0158] Step 2-4: The microprocessor 116 outputs the control signal
136 for the gain switching to the gain switching circuit 133
according to the calculated value of V1t.
[0159] Step 2-5: The microprocessor 116 outputs control signals
124, 125 and 126 to each of drive circuits 119, 120 and 121 so that
the switch 101 and switch 102 are in the continuous turning-on
status, and the switch 103 is in the continuous turning-off
status.
[0160] Step 2-6: The switch 101 and switch 102 are in the
continuous turning-on status, and the switch 103 is in the
continuous turning-off status.
[0161] Step 2-7: The electric energy is delivered to the patient in
the positive phase waveform. The voltage of the electric energy
storage section 104 is decreased.
[0162] Step 2-8: When the voltage of the electric energy storage
section 104 is decreased to the V1t, the microprocessor 116 outputs
control signals 124, 125 and 126 to each of drive circuits 119, 120
and 121 so that the switch 101 and switch 102 are in the continuous
turning-off status, and the switch 103 is in the continuous
turning-on status.
[0163] Step 2-9: The switch 101 and switch 102 are in the
continuous turning-off status, and the switch 103 is in the
continuous turning-on status.
[0164] Step 2-10: The microprocessor 116 outputs the voltage signal
138 of the discharge voltage reference curve which is previously
stored in the ROM 141.
[0165] Step 2-11: The error amplifier 142 of the pulse width
modulation circuit 143 compares the voltage signal 138 of the
reference curve to the voltage signal 137 of the electric energy
storage section 104, and outputs the signal 139 to control the rate
of the on (turning-on)-time of the switch 101 so that the voltage
of the electric energy storage section 104 is equal to the
reference curve to the drive circuit 119 of the switch 101.
[0166] Step 2-12: The switch 101 conducts the switching operation
at the rate of the on (turning-on) time determined in Step
2-11.
[0167] Step 2-13: The energy is delivered to the patient 113 in the
negative phase waveform. The voltage of the electric energy storage
section 104 is decreased.
[0168] Step 2-14: When the voltage of the electric energy storage
section 104 is lowered to the second phase (negative phase) end
voltage V2t, the microprocessor 116 outputs the control signal 124
to the drive circuit 119 of the switch 101 so that the switch 101
is in the continuous turning-off status.
[0169] Step 2-15: The energy output to the patient 113 is
completed.
[0170] The Third Embodiment
[0171] In the electrotherapy apparatus according to the present
embodiment, the structure is the same as the second embodiment
shown in FIG. 5, and only the electric energy delivering method is
different, and the method is detailed below.
[0172] This electric energy delivering method is a method which
output controls so that the current which is increased
corresponding to the energy amount outputted from the electric
energy storage section 104, is increased corresponding to the
function of the predetermined time and current (Step 3-1-Step
3-15). Here, the current which flows from the electric energy
accumulation section 14 is converted into the corresponding voltage
by the current monitoring circuit 131. For this reason, the
function of the predetermined time and current is previously
converted into the function of time and voltage corresponding to
the current. The converted function is used as the discharge
current reference curve.
[0173] Step 3-1: Charging to the electric energy storage section
104 is completed. At this time, switches 101, 102 and 103 are in
the turning-off status.
[0174] Step 3-2: By the pressing of the discharge start button(not
shown) by the operator, the discharge start command is inputted
into the micro processor 116.
[0175] Step 3-3: The microprocessor 116 calculates the discharging
end voltage V1t of the first phase (positive phase) and the
discharging end voltage V2t of the second phase (negative phase)
from the voltage of the electric energy storage section 104 at this
time.
[0176] Step 3-4: The microprocessor 116 outputs the control signal
136 for the gain switching to the gain switching circuit 133
according to the calculated value of V1t.
[0177] Step 3-5: The microprocessor 116 outputs control signals
124, 125 and 126 to each of drive circuits 119, 120 and 121 so that
the switch 101 and switch 102 are in the continuous turning-on
status, and the switch 103 is in the continuous turning-off
status.
[0178] Step 3-6: The switch 101 and switch 102 are in the
continuous turning-on status, and the switch 103 is in the
continuous turning-off status.
[0179] Step 3-7: The electric energy is delivered to the patient
113 in the positive phase waveform. The voltage of the electric
energy storage section 104 is decreased.
[0180] Step 3-8: When the voltage of the electric energy storage
section 104 is decreased to the V1t, the microprocessor 116 outputs
control signals 124, 125 and 126 to each of drive circuits 119, 120
and 121 so that the switch 101 and switch 102 are in the continuous
turning-off status, and the switch 103 is in the continuous
turning-on status.
[0181] Step 3-9: The switch 101 and switch 102 are in the
continuous turning-off status, and the switch 103 is in the
continuous turning-on status.
[0182] Step 3-10: The microprocessor 116 outputs the voltage of the
discharge current reference curve which is previously stored in the
ROM 141.
[0183] Step 3-11: The error amplifier 142 of the pulse width
modulation circuit 143 compares the voltage of the current
reference curve to the voltage converted from the current which
flows from the electric energy storage section 104 by the current
monitoring circuit 131, and outputs the signal 139 to control the
rate of the on (turning-on)-time of the switch 101 so that the both
voltages are equal, to the drive circuit 119 of the switch 101.
[0184] Step 3-12: The switch 101 conducts the switching operation
at the rate of the on (turning-on)-time determined in Step
3-11.
[0185] Step 3-13: The energy is delivered to the patient 113 in the
negative phase waveform. The voltage of the electric energy storage
section 104 is decreased.
[0186] Step 3-14: When the voltage of the electric energy storage
section 104 is lowered to the second phase (negative phase) end
voltage V2t, the microprocessor 116 outputs the control signal to
the drive circuit 119 of the switch 101 so that the switch 101 is
in the continuous turning-off status.
[0187] Step 3-15: The energy output to the patient 113 is
completed.
[0188] Examples of the output waveform of the electrotherapy
apparatus in the first to third embodiments are shown in FIG. 6(a)
to (d).
[0189] The Common Structure of Fourth to Sixth Embodiments
[0190] FIG. 7 is a block structural view showing the electrotherapy
apparatus 150 according to the fourth to sixth embodiments of the
present invention. As shown in FIG. 7, in the electrotherapy
apparatus 150, a load voltage monitoring circuit 161, load current
monitoring circuit 162, and further, the reference voltage
generating circuit 164 in the pulse width modulation circuit 143
are added to the electrotherapy apparatus according to the second
embodiment.
[0191] The common part to that of FIG. 1 to 5 is shown by the same
numeral code, and its explanation is omitted.
[0192] Further, FIG. 8 is a view showing examples of the preferable
reference curves of the voltage of the electric energy storage
section 104 and the current which flows from the electric energy
storage 104 (In case of current reference curve, the current is
converted into voltage by the current monitoring circuit). FIG. 9
is a view showing an example of the relationship of the impedance
of the patient and the output voltage waveform.
[0193] As shown in FIG. 8, as the reference curve, it is preferable
to use the voltage value Vcap, voltage differential value d/dt
(Vcap), voltage double differential value d/dt (d/dt Vcap), current
value Icap, current differential value d/dt (Icap), and current
double differential value d/dt (d/dt Icap).
[0194] In FIG. 9, Rp is the impedance of the patient, and the
output voltage waveforms (the first phase and the second phase) in
the case of the standard impedance r, smaller impedance (1/2) r,
and larger impedance (5/2) r, are shown.
[0195] As shown in FIG. 9, the larger the impedance of the patient
is, the longer is the duration of the truncated exponential
waveform of the first phase.
[0196] Further, when the electric power of the second phase
waveform is controlled according to the reference curve of the
voltage value Vcap, the necessary energy can be supplied in a
predetermined time period, without depending on the impedance of
the patient. That is, as shown in the view, because the larger the
impedance of the patient is, the higher the amplitude of the
outputted output voltage is, the output electric power waveform
becomes constant without depending on Rp.
[0197] The Fourth Embodiment
[0198] The electrotherapy apparatus according to the present
embodiment has a patient parameter measuring means for measuring
the patient parameter, and an output electrode parameter measuring
means (the load voltage monitoring circuit 161, load current
monitoring circuit 162) for measuring the voltage generated between
output electrodes or the current flowing to the output
electrode.
[0199] The electrotherapy apparatus has a control means for
controlling so that the electric power of the electric energy
becomes constant without depending on the value of the patient
parameter, according to the patient parameter measured by the
patient parameter measuring means before the second phase waveform
is outputted, and to the value relating to the voltage between the
output electrodes, or the value relating to the current flowing to
the output electrode, measured by the output electrode parameter
measuring means during the output of the second phase waveform.
[0200] That is, the present embodiment uses the patient impedance
measured before the second phase (negative phase) output and the
patient voltage (or current) during the second phase (negative
phase) output.
[0201] The present embodiment is used in the case where, as the
patient parameter measuring means, the patient impedance is
calculated from the change of the output signal 122 form the
voltage monitoring circuit 114 during the first phase output.
[0202] Referring to FIG. 7 to FIG. 9, the patient parameter
measuring method and the electric energy delivering method to the
patient by the electrotherapy apparatus according to the present
embodiment, will be detailed below.
[0203] Step 4-1: Charging to the electric energy storage section
104 is completed. At this time, switches 101, 102 and 103 are in
the turning-off status.
[0204] Step 4-2: By the pressing of the discharge start button(not
shown) by the operator, the discharge start command is inputted
into the micro processor 116.
[0205] Step 4-3: The microprocessor 116 calculates the discharging
end voltage V1t of the first phase (positive phase) and the
discharging end voltage V2t of the second phase (negative phase)
from the voltage of the electric energy storage section 104 at this
time.
[0206] Step 4-5: The microprocessor 116 outputs control signals
124, 125 and 126 to each of switch drive circuits 119, 120 and 121
so that the switch 101 and switch 102 are in the continuous
turning-on status, and the switch 103 is in the continuous
turning-off status.
[0207] Step 4-6: The switch 101 and switch 102 are in the
continuous turning-on status, and the switch 103 is in the
continuous turning-off status.
[0208] Step 4-7: The electric energy is delivered to the patient
113 in the positive phase waveform. The voltage of the electric
energy storage section 104 is decreased. The output signal 122 from
the voltage monitoring circuit 114 during the first phase waveform
output is inputted to the microprocessor 116, and from the rate of
its time change, the microprocessor 116 calculates the impedance of
the patient 113 (corresponding to the patient parameter
measurement).
[0209] Step 4-8: When the voltage of the electric energy storage
section 104 is decreased to the V1t, the microprocessor 116 outputs
control signals 124, 125 and 126 to each of drive circuits 119, 120
and 121 so that the switch 101 and switch 102 are in the continuous
turning-off status, and the switch 103 is in the continuous
turning-on status.
[0210] Step 4-9: The switch 101 and switch 102 are in the
continuous turning-off status, and the switch 103 is in the
continuous turning-on status.
[0211] The microprocessor 116 outputs the gain switching signal 136
determined by the calculated patient impedance and the voltage of
the electric energy storage section 104 at the time of the output
start of the first phase (positive phase), which is monitored by
the voltage monitoring circuit 114 and outputted, to the gain
switching circuit 133.
[0212] Step 4-11: The error amplifier 142 of the pulse width
modulation circuit 143 compares the output signal 137 of the gain
switching circuit 133 by the gain switched output signal 173 of the
load voltage monitoring circuit 161 of the patient (corresponding
to the value relating to the voltage between the output
electrodes), or the gain switched output signal 174 of the load
current monitoring circuit 162 of the patient (corresponding to the
value relating to the current flowing to the output electrode)to
the constant output voltage from the reference voltage generation
circuit 164, and outputs the signal 139 to control the rate of the
on (turning-on)-time of the switch 101 so that the voltage of the
output signal 137 of the gain switching circuit 133 is equal to the
constant output voltage from the reference voltage generation
circuit 164, to the drive circuit 119 of the switch 101.
[0213] Step 4-12: The switch 101 conducts the switching operation
at the rate of the on (turning-on)-time determined in Step
4-11.
[0214] Step 4-13: The energy is delivered to the patient 113 in the
negative phase waveform. The voltage of the electric energy storage
section 104 is decreased.
[0215] Step 4-14: When the voltage of the electric energy storage
section 104 is lowered to the second phase (negative phase)
discharging end voltage V2t, the microprocessor 116 outputs the
control signal 124 to the drive circuit 119 of the switch 101 so
that the switch 101 is in the continuous turning-off status.
[0216] Step 4-15: The energy output to the patient 113 is
completed.
[0217] In the present embodiment, the constant output voltage from
the reference voltage generation circuit 164 is always constant,
without depending on the impedance of the patient 113, and the
large and small value of the energy supplied to the patient
113.
[0218] The Fifth Embodiment
[0219] The electrotherapy apparatus according to the present
embodiment has the patient parameter measuring means for measuring
the patient parameter, and the output electrode parameter measuring
means (load voltage monitoring circuit 161, load current monitoring
circuit 162) for measuring the voltage generated between the output
electrodes or the current flowing to the output electrode.
[0220] The control means of the present embodiment controls so that
the electric power of the electric energy becomes constant without
depending on the value of the patient parameter, according to the
patient parameter measured by the patient parameter measuring means
before the second phase waveform is outputted, and to the value
relating to the voltage between output electrodes or the value
relating to the current flowing to the output electrode, measured
by the output electrode parameter measuring means during the output
of the second phase waveform.
[0221] That is, this control means is a control method by which the
impedance of the patient measured before the output of the second
phase (negative phase) and the voltage (or current) of the patient
during the output of the second phase (negative phase), are used,
and the patient parameter measuring means is used in the case where
the impedance of the patient is calculated by using the high
frequency micro current.
[0222] Referring to FIG. 7 to FIG. 9, the patient parameter
measuring method and the electric energy delivering method to the
patient by the electrotherapy apparatus according to the present
embodiment, will be detailed below.
[0223] Step 5-1: Charging to the electric energy storage section
104 is completed. At this time, switches 101, 102 and 103 are in
the turning-off status. The high frequency micro current circuit
163 supplies the high frequency micro current to the patient 113
through the electrodes 112a and 112b, and the feedback signal from
the patient 113 to the supplied high frequency micro current is
detected and processed, and the processed signal 175 is outputted
to the microprocessor 116.
[0224] Step 5-2: According to the pressing of the discharge start
button (not shown) by the operator, the discharge start command is
inputted into the micro processor 116. The microprocessor 116
calculates the impedance of the patient from the output signal 175
from high frequency micro current circuit 163 (corresponding to the
patient parameter measuring means).
[0225] Step 5-3: The microprocessor 116 calculates the discharging
end voltage V1t of the first phase (positive phase) and the
discharging end voltage V2t of the second phase (negative phase)
from the voltage of the electric energy storage section 104 at this
time.
[0226] Step 5-5: The microprocessor 116 outputs control signals
124, 125 and 126 to each of the switch drive circuits 119, 120 and
121 so that the switch 101 and switch 102 are in the continuous
turning-on status, and the switch 103 is in the continuous
turning-off status.
[0227] Step 5-6: The switch 101 and switch 102 are in the
continuous turning-on status, and the switch 103 is in the
continuous turning-off status.
[0228] Step 5-7: The electric energy is delivered to the patient
113 in the positive phase waveform. The voltage of the electric
energy storage section 104 is decreased.
[0229] Step 5-8: When the voltage of the electric energy storage
section 104 is decreased to the V1t, the microprocessor 116 outputs
control signals 124, 125 and 126 to each of the switch drive
circuits 119, 120 and 121 so that the switch 101 and switch 102 are
in the continuous turning-off status, and the switch 103 is in the
continuous turning-on status.
[0230] Step 5-9: The switch 101 and switch 102 are in the
continuous turning-off status, and the switch 103 is in the
continuous turning-on status.
[0231] The microprocessor 116 outputs the gain switching signal
136, determined by the calculated impedance of the patient 113 and
the voltage of the electric energy storage section 104 at the time
of the output start of the first phase, which is monitored and
outputted by the voltage monitoring circuit 114, to the gain
switching circuit 133.
[0232] Step 5-11: The error amplifier 142 of the pulse width
modulation circuit 143 compares the output signal 137 of the gain
switching circuit 133 by the gain switched output signal 173 of the
load voltage monitoring circuit 161 of the patient (corresponding
to the value relating to the voltage between electrode), or the
gain switched output signal 174 of the load current monitoring
circuit 162 of the patient (corresponding to the value relating to
the current flowing to the output electrode), to the constant
output voltage from the reference voltage generation circuit 164,
and outputs the signal 139 to control the rate of the on
(turning-on)-time of the switch 101 so that the voltage of the
output signal 137 of the gain switching circuit 133 is equal to the
constant output voltage from the reference voltage generation
circuit 164, to the drive circuit 119 of the switch 101.
[0233] Step 5-12: The switch 101 conducts the switching operation
at the rate of the on (turning-on)-time determined in Step
5-11.
[0234] Step 5-13: The energy is delivered to the patient 113 in the
negative phase waveform. The voltage of the electric energy storage
section 104 is decreased.
[0235] Step 5-14: When the voltage of the electric energy storage
section 104 is lowered to the second phase (negative phase)
discharging end voltage V2t, the microprocessor 116 outputs the
control signal 124 to the drive circuit 119 of the switch 101 so
that the switch 101 is in the continuous turning-off status.
[0236] Step 5-15: The energy output to the patient 113 is
completed.
[0237] The Sixth Embodiment
[0238] The electrotherapy apparatus according to the present
embodiment has the patient parameter measuring means for measuring
the patient parameter, and the output electrode parameter measuring
means (load voltage monitoring circuit 161, load current monitoring
circuit 162) for measuring the voltage generated between the output
electrodes or the current flowing to the output electrode.
[0239] The control means of the present embodiment controls the
switching operation of the switch, according to the patient
parameter measured by the patient parameter measuring means before
the second phase waveform is outputted, and to the value relating
to the voltage between output electrodes or the value relating to
the current flowing to the output electrode, measured by the output
electrode parameter measuring means during the output of the second
phase waveform.
[0240] That is, this control method is a control method by which
the impedance of the patient measured before the output of the
second phase (negative phase) and the voltage (or current) of the
patient during the output of the second phase (negative phase), are
used, and the patient parameter measuring means is used in the case
where the impedance of the patient is calculated by using the
patient voltage and the patient current.
[0241] Referring to FIG. 7 to FIG. 9, the patient parameter
measuring method and the electric energy delivering method to the
patient by the electrotherapy apparatus according to the present
embodiment, will be detailed below.
[0242] Step 6-1: Charging to the electric energy storage section
104 is completed. At this time, switches 101, 102 and 103 are in
the turning-off status.
[0243] Step 6-2: According to the pressing of the discharge start
button (not shown) by the operator, the discharge start command is
inputted into the micro processor 116.
[0244] Step 6-3: The microprocessor 116 calculates the discharging
end voltage (V1t) of the first phase (positive phase) and the
discharging end voltage (V2t) of the second phase (negative phase)
from the voltage of the electric energy storage section 104 at this
time.
[0245] Step 6-5: The microprocessor 116 outputs control signals
124, 125 and 126 to each of the switch drive circuits 119, 120 and
121 so that the switch 101 and switch 102 are in the continuous
turning-on status, and the switch 103 is in the continuous
turning-off status.
[0246] Step 6-6: The switch 101 and switch 102 are in the
continuous turning-on status, and the switch 103 is in the
continuous turning-off status.
[0247] Step 6-7: The electric energy is delivered to the patient in
the positive phase waveform. The voltage of the electric energy
storage section 104 is decreased.
[0248] The output signal 171 from the load voltage monitoring
circuit 161 of the patient during the output of the first phase,
and the output signal 172 from the load current monitoring circuit
162 of the patient are inputted into the microprocessor 116, and
the microprocessor 116 calculates the impedance of the patient 113
by using these signals (corresponding to the measurement of the
patient parameter).
[0249] Step 6-8: When the voltage of the electric energy storage
section 104 is decreased to the V1t, the microprocessor 116 outputs
control signals 124, 125 and 126 to each of the switch drive
circuits 119, 120 and 121 so that the switch 101 and switch 102 are
in the continuous turning-off status, and the switch 103 is in the
continuous turning-on status.
[0250] Step 6-9: The switch 101 and switch 102 are in the
continuous turning-off status, and the switch 103 is in the
continuous turning-on status.
[0251] The microprocessor 116 outputs the gain switching signal
136, determined by the calculated impedance of the patient and the
voltage of the electric energy storage section 104 at the time of
the output start of the first phase, which is monitored and
outputted by the voltage monitoring circuit 114, to the gain
switching circuit 133.
[0252] Step 6-10: The error amplifier 142 of the pulse width
modulation circuit 143 compares the output signal 173 of the gain
switched load voltage monitoring circuit 161 of the patient
(corresponding to the value relating to the voltage between the
output electrodes), or the output signal 137 of the gain switching
circuit 133 by the gain switched load current monitoring circuit
162 of the patient (corresponding to the value relating to the
current flowing to the output electrode), to the constant output
voltage from the reference voltage generation circuit 164, and
outputs the signal 139 to control the rate of the on
(turning-on)-time of the switch 101 so that the voltage of the
output signal 137 of the gain switching circuit 133 is equal to the
constant output voltage from the reference voltage generation
circuit 164, to the drive circuit 119 of the switch 101.
[0253] Step 6-11: The switch 101 conducts the switching operation
at the rate of the on (turning-on)-time determined in Step
2-11.
[0254] Step 6-12: The energy is delivered to the patient 113 in the
negative phase waveform. The voltage of the electric energy storage
section 104 is decreased.
[0255] Step 6-13: When the voltage of the electric energy storage
section 104 is lowered to the second phase (negative phase)
discharging end voltage V2t, the microprocessor 116 outputs the
control signal 124 to the drive circuit 119 of the switch 101 so
that the switch 101 is in the continuous turning-off status.
[0256] 6-14: The energy output to the patient 113 is completed.
[0257] In the present embodiment, the same reference curve as in
the other embodiments is not used. Alternatively, the reference
voltage which is independent of the impedance of the patient or the
delivering energy, is used.
[0258] Further, according to the impedance of the patient and the
delivering energy, the gain of the comparative object (the voltage
of the patient or the current of the patient) of the reference
voltage is set.
[0259] Incidentally, in each of the first to sixth embodiment, when
the electric energy stored in the electric energy storage section
104 is delivered onto the patient 113 in the first phase (positive
phase) waveform and the second phase (negative phase) waveform,
initially, the necessary electric energy is delivered in the first
phase (positive phase) waveform, next, from the remained energy,
the necessary electric energy can be delivered in the second phase
(negative phase) waveform for a predetermined time period, and
further, the multiphasic waveform by which the electric energy
stored in the electric energy storage section is delivered onto the
patient 113 in the first phase (positive phase) waveform and the
second phase (negative phase) waveform by alternately repeating
them a plurality of times, can be easily realized (the waveform in
FIG. 6(d)).
[0260] Further, in the above-described embodiments, in the first
phase, the truncated exponential waveform, and in the second phase,
the electric power control waveform according to the reference
curve are outputted, however, alternatively, in the first phase,
initially, the electric power control waveform, and next, in the
second phase, the truncated exponential waveform may be
outputted.
[0261] When the multiphasic waveform is outputted, it can be
appropriately selected whether, in the third phase and the
subsequent, the truncated exponential waveform is outputted, or the
electric power control waveform is outputted.
[0262] Further, the stimulation pulse applied onto the patient,
described in the above embodiments, is appropriate for terminating
the fibrillation of the heart in cardiac disease, however, to the
other medical treatments in which the high voltage electric
stimulation pulse is required, the electrotherapy apparatus of the
present invention can be applied.
[0263] As detailed above, according to the first aspect of the
invention, the apparatus has the electric energy storage section to
generate the stimulation pulse, and the output electrode to apply
the stimulation pulse to the patient, and it structured in such a
manner that the polarity of the voltage outputted to the output
electrode is reversed, and is structured such that at least the
first phase waveform and the second phase waveform of the electric
energy are outputted from the output electrode, and the shape of
the second phase waveform of the electric energy can be controlled,
thereby, the output waveform of the second phase (negative phase)
can be freely set without depending on the voltage (V1t) of the
electric energy storage section at the time of the start of the
second phase (negative phase). That is, the second phase (negative
phase) output voltage (the hither voltage than V1t can be
outputted), output current, and output electric power can be freely
set, and further, the electrotherapy apparatus by which the
necessary energy can be delivered within an arbitrary time period,
can be provided.
[0264] According to the electrotherapy apparatus of the second
aspect of the invention, the apparatus has the electric energy
storage section to generate the stimulation pulse, and the output
electrode to apply the stimulation pulse to the patient, and it
structured in such a manner that the polarity of the voltage
outputted to the output electrode is reversed, and is structured
such that at least the first phase waveform and the second phase
waveform of the electric energy are outputted from the output
electrode, and by the outputted second phase waveform of the
electric energy, the necessary electric energy is delivered within
a predetermined time period, thereby, the predetermined second
phase (negative phase) waveform of the electric energy can be
delivered to the patient within an optimum time period for the
defibrillation without depending on the impedance of the patient,
and the electrotherapy apparatus having high success rate for
defibrillation can be provided.
[0265] According to the electrotherapy apparatus of the third to
seventh aspect of the invention, by controlling the electric
parameters relating to the energy storage section, which vary
corresponding to the delivering amount of the electric energy, the
delivering energy can be controlled.
[0266] According to the electrotherapy apparatus of the eighth
aspect of the invention, according to the patient parameter before
the second phase waveform output and the electric parameters on the
output electrode during the second phase waveform output, the
electric power of the output energy can be controlled.
[0267] According to the electrotherapy apparatus of the ninth
aspect of the invention, the biphasic defibrillator (electrotherapy
apparatus) can be structured by one (capacitor) electric energy
storage section, thereby, the second phase output waveform can be
freely set.
[0268] According to the electrotherapy apparatus of the tenth
aspect of the invention, by the simple control method, the second
phase output waveform can be freely set.
[0269] According to the electrotherapy apparatus of the eleventh
aspect of the invention, by the simple control method, the first
phase and the second phase can be formed.
[0270] According to the electrotherapy apparatus of the twelfth
aspect of the invention, by the electric control, the high speed
opening/closing of each switch means can be conducted.
[0271] According to the electrotherapy apparatus of the thirteenth
aspect of the invention, by controlling the shape of the pulse
waveform, the apparatus is structured so that the necessary energy
can be outputted within a constant time period, thereby, the
effective energy can be delivered within the effective stimulation
period.
[0272] According to the electrotherapy apparatus of the fourteenth
aspect of the invention, by controlling so that the electric power
becomes constant, independently of the value even when the
impedance of the patient is low or high, the stimulation pulse
having the effective energy amount can be applied.
[0273] According to the electrotherapy apparatus of the fifteenth
to eighteenth aspect of the invention, when the electric parameters
relating to the energy storage section which vary corresponding to
the energy supply amount are controlled, the delivering energy can
be controlled.
[0274] According to the electrotherapy apparatus of the nineteenth
aspect of the invention, the electric power of the output energy
can be controlled, according to the patient parameter before the
output of the second phase waveform and the electric parameters on
the output electrode during the output of the second phase
waveform.
[0275] According to the electrotherapy apparatus of the twentieth
aspect of the invention, when the switch in the electric circuit is
continuously switching-operated by the pulse width modulation
system, the electric power can be controlled so that the necessary
energy is delivered.
[0276] According to the electrotherapy apparatus of the twenty
first aspect of the invention, by controlling according to the
stored reference curve, the stimulation pulse having the
predetermined shape can be applied.
[0277] According to the electrotherapy apparatus of the twenty
second to twenty third aspect of the invention, by controlling the
electric parameters relating to the energy storage section which
vary corresponding to the energy delivering amount according to the
reference curve, the delivering energy can be controlled.
[0278] According to the electrotherapy apparatus of the twenty
fourth aspect of the invention, by controlling so that the electric
power becomes constant independently of the value even when the
impedance of the patient is low or high, the stimulation pulse
having the effective energy amount can be applied.
[0279] According to the electrotherapy apparatus of the twenty
fifth aspect of the invention, the electric power of the output
energy can be controlled, according to the patient parameter before
the second phase waveform output and the electric parameters on the
output electrode during the second phase waveform output.
[0280] According to the electrotherapy apparatus of the twenty
sixth aspect of the invention, by controlling so that the electric
power becomes constant independently of the value even when the
impedance of the patient is low or high, the stimulation pulse
having the effective energy amount can be applied.
[0281] According to the electrotherapy apparatus of the twenty
seventh aspect of the invention, because the apparatus is
structured in such a manner that the electric energy is supplied to
the inductor, the shape of the waveform of the stimulation pulse
can be controlled with the high degree of freedom.
[0282] According to the electrotherapy apparatus of the twenty
eighth aspect of the invention, a predetermined energy amount in
the energy stored in the electric energy storage section can be
supplied to the inductor.
[0283] According to the electrotherapy apparatus of the twenty
ninth aspect of the invention, by controlling the energy by
supplying it to the inductor, even when the patient has the high
impedance, the energy can be supplied while the voltage is made
higher than the voltage value of the capacitor which is the
electric energy storage section, at need.
[0284] According to the electrotherapy apparatus of the thirtieth
aspect of the invention, by conducting the switching control, the
energy stored in the capacitor is supplied once to the inductor,
and then, can be supplied to output electrode.
[0285] According to the electrotherapy apparatus of the thirty
first aspect of the invention, the switching is controlled by pulse
width modulation control, therefore, the electric power can be
controlled.
[0286] According to the electrotherapy apparatus of the thirty
second aspect of the invention, by controlling so that the electric
power becomes constant, independent of the value even when the
impedance of the patient is low or high, the stimulation pulse
having the effective energy amount can be applied.
[0287] According to the electrotherapy apparatus of the thirty
third aspect of the invention, by controlling according to the
stored reference curve, the stimulation pulse having the
predetermined shape can be applied.
[0288] According to the electrotherapy apparatus of the thirty
fourth to thirty fifth aspect of the invention, when the electric
parameters relating to the energy storage section which vary
corresponding to the energy delivering amount are controlled
according to the reference curve, the delivering energy can be
controlled.
[0289] According to the electrotherapy apparatus of the thirty
sixth aspect of the invention, the apparatus has the charging
circuit, thereby, when the energy is consumed by use, the apparatus
can be used again.
[0290] According to the electrotherapy apparatus of the thirty
seventh, or thirty eighth aspect of the invention, the biphasic
electric stimulation pulse waveform can be freely outputted,
thereby, the electrotherapy apparatus which is effective in
terminating the fibrillation in the cardiac diseases, can be
provided.
[0291] According to the electrotherapy apparatus of the thirty
ninth aspect of the invention, the apparatus is an external type
apparatus which can apply the stimulation pulse from the outside of
the patient, thereby, the same apparatus can be used for the
different patient.
[0292] According to the electric energy delivering method of the
electrotherapy apparatus of the fortieth aspect of the invention,
when the electric energy stored in the electric energy storage
section is delivered to the patient in biphasic waveform,
initially, the necessary electric energy is delivered in the first
phase waveform, and next, the necessary electric energy is
delivered from the remained energy, in the second phase waveform
within a predetermined time period, thereby, predetermined electric
energy can be delivered in the second phase waveform to the patient
within the optimum time period for the defibrillation, without
depending on the impedance of the patient.
[0293] According to the electric energy delivering method of the
electrotherapy apparatus of the forty first aspect of the
invention, when the electric energy stored in the electric energy
storage section is repeatedly delivered onto the patient at the
plurality of times alternately (multiphasic output waveform), by
using the first phase waveform and the second phase waveform, by
freely forming the shape of the second phase waveform without
depending on the impedance of the patient, there is a possibility
that the more effective defibrillation can be conducted.
[0294] In the electrotherapy apparatus shown by the present
invention, when the power has been turned on, more than 98% of the
energy stored in the energy storage section can be outputted, and
the efficiency of use is very high, and this is advantageous for
the reduction of the apparatus size and weight.
[0295] Further, because the energy stored in the energy storage
section is used, it is not necessary to electrically isolate
respectively and supply the energy, for the output of the second
phase.
[0296] Further, because the instantaneous maximum electric power as
the power source is determined by the internal resistance of the
capacitor used in the energy storage section, it is not necessary
to have the power source with the large electric power, and the
reduction of size and weight can be realized.
[0297] In the electrotherapy apparatus shown by the present
invention, in order to output the second phase waveform, as a means
for storing the energy once, the inductor 105 is used (stored as
the magnetic energy), thereby, even when the voltage is higher or
lower than the voltage of the charging capacitor (energy storage
section 104), the output can be conducted.
[0298] The feature of this invention is specifically effective for
the external type defibrillator. This is for the reason that the
impedance of the patient to which the external type defibrillator
is applied, has the large distribution depending on the difference
of the physical feature of each patient. However, this feature of
the present invention could be also applied to the internal type
defibrillator.
[0299] Because the electrotherapy apparatus of the present
invention can outputs the biphasic waveform by one capacitor,
additional circuit elements (switches of H bridge) are not
necessary, thereby, the reduction of the size and weight can be
realized. Further, by the electric power control, the voltage of
the second phase can be set to the optimum value which is
considered for the inherency of the impedance of the patient.
* * * * *